Outlet box



Nov. 12, 1929. J, J. MERRILL OUTLET BOX Filed Aug.- 18. 1921 3Sheets-Sheet 1 Nov. 12, 1929. MERRILL 1,735,331

OUTLET BOX Filed Aug. 18. 1921 5 Sheets-Sheet 2 Nov. 12, 1929. J,MERRILL OUTLET BOX Filed Aug; 18, 1921 3 Sheets-Sheet 3 Patented Nov.12, 1929 UNITED STATES PATENT OFFICE JOHN J. MERRILL, 0F IPSWICH,MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGNMENTS, TO ELECTRIC OUTLETCOMPANY, INC, OF NEW YORK, N. 'Y., A CORPORATION 01' NEW YORK OUTLETIBOX Application filed August 18, 1921.

This invention relates to outlet boxes or similar devices for supportingelectric fixtures or switches on a lath and plaster wall or ceiling,which has already been erected.

Prior to my invention the supporting means which have been employed forlath and plaster walls, or ceilings, in practice, have not, so far as Iam aware, been satisfactory, principally, for the reason that theplaster surface provides an insecure support for a metal base plate orthe like, as the plaster is liable to crumble, and laths aflord anunplastering which it engages, or to cause damage to the plasteradjacent thereto.

I accomplish this object by providing a form of box or casing which isadapted to be inserted into an opening between alternate laths formed byremoving a section of the intervening lath, and to be held-in positionby clamping the lath and plaster wall between clamping members thereon,said members extending over suflicient area to avoid danger of injury tothe plaster.

For a more complete understanding of my invention reference is made tothe accompanying drawing in which:

Fig. 1 is a sectional View. at the line 1-1 of Fig. 2, of a preferredembodiment of my invention. in position in a wall.

Fig. 2 is a plan view thereof from the back side of the wall.

Fig. 3 is a similar view from the front side of the wall, or from withinthe room.

Serial No. 498,274.

Fig. 4 is a transverse section, at line 44 of Fig. 2.

Fig. 5 is a detail perspective view of the wlire clamping means which Ipreferably emp oy.

Fig. 6 is a detail sectional view of the fixture supporting nipple.

Fig. 7 is an elevation illustrating the manner of placing the casing inposition in a wall.

Fig. 8 is a sectional view at line 88 of Fig. 9 illustrating a slightlymodified form of the invention.

Fig. 9 is a plan view from the inner side of a lath and plaster ceiling.

Fig. 10 is a detail view of the bridge plate which I employ undercertain conditions.

Fig. 11 is a detail view of a metal covered conductor clamp.

According to my invention, I provide a box or casing of sheet metal ofapproximately square form, comprising the end walls, a, a, and sidewalls I), b, and a bottom 0 which is connected thereto by interlockingthe edges or by other suitable means. The end walls a are extendedbeyond the side walls I) at the bottom side, and the edges thereof arecurved or bevelled from the inner edges of the sidewalls to the middleportion thereof, the bottom, which is attached to said edges, beingsimilarly shaped so that the portion of the casing beyond the inneredges of the sides Z), 6 has bevelled or curved sides and flat ends. Theend portions of the strip of material, of which the bottom 0 is formed,are extended outward at right angles or perpendicularly to the sidewalls, 6, to form flanges 01, said flanges extending throughout thelength of the side walls and having rounded corners.

A clamping plate 6 is provided having a square or rectangular aperturetherein, which is adapted to receive the walls a, a and b, b of thecasing, so that it may slide freely thereon, and aligning apertures areprovided in said plate and in the flanges d, to receive clampin screwsf, the apertures in the flanges being screw threaded therefor.

In the formation of the casing sides and bottom, circular portions arestruck out, and practically severed from the adjacent metal, withoutactually removing said portions, so that they may be easily pushed outfrom within the casing, to form apertures thru which the heavilyinsulated conductors, which are located between the inner and outerwalls,

may be passed into the casing, where they will be connected to thefixture wires. In order that the conductors may be drawn into the casingat any convenient point, a pair of circular, severed portions 0 areprovided in each side portion of the curved or bevelled bottom a and asimilar pair of circular portions (1., are formed in each of the endwalls a, in the rear of the flanges d and closely adjacent the planethereof.

A clamping frame g, for the wires, after they are inserted, is providedwithin casing, said frame being of the same rectangular form as thesides of the casing and adapted to be adjusted to and from the bottomthereof. Arms h, having inwardly bent portions, are extended from theinner sides of the frame, and screws 2' are passed thru said endportions and threaded in the bottom of the casing, to hold said frame inclamping position.

The middle portion of the bottom 0 is provided with an aperture in whicha nipple j is inserted, said nipple being externally screw threaded andhaving a flange j at one end, which is clamped against the back or outerside of the bottom by a nut is, which is screwed on to the nippleagainst the inner side of the bottom. To hold the nipple from turning,when the nut k is tightened, a lug j is provided on the flange j, whichengages in an aperture 0 formed in the bottom 0, as shown in Fig. 6 Thebottom 0 has its middle portion flattened and inwardly dished orbevelled about the nipple receiving aperture therein, and the surface ofthe flange j which engages the bottom is slightly rounded and bevelled,so that the angular position in which the nipple is clamped in theaperture of the bottom may be somewhat varied.

As previously stated, the above described device is primarily designedfor installation in a lath and plaster wall or ceiling, alreadyconstructed, as distinguished from an installation in a building inprocess of construction, and, in practice, is so formed that thedistance between the exterior surfaces of the side walls I; areapproximately equal to the width of an ordinary lath, plus twice thewidth of the space between two laths. When the casing is installed, asection of one lath, as w, is sawed therefrom, which is equal in lengthto the distance between the end walls a, and which, in practice, ispreferably the same as the distance between the side walls I), so that,when the plaster is removed,

a square hole is formed in the wall or cening, which is bounded by thesevered ends of the lath w, from which the piece has been removed, andthe edges of the two adjacent laths y and z. I

When the casing is to be inserted in the hole thus formed, the screws fand plate e are entirely removed, and the casing is held by the nipple jin such a position that one of the flanges d is first inserted. Then thecasing is moved inwardly and swung laterally towards one side of thehole until the other flange is carried in past the opposite side of thehole, and then the casing is swung so that its sides are perpendicularto the laths, and drawn outward, so that the square portion of thecasing is inserted in the hole and the flanges d engage the inner sidesof the adjacent laths y' and 2, as indicated in Fig. 7. As the casingshould be made as deep as conditions permit, the beveled orapproximately cylindrical construction of the bottom of the casing isimportant, as it enables the casing to be placed in position in the wallfrom within the room of the building, notwithstanding the narrow spacewhich is usually provided between the inner and outer wall thereof,

and, at the same time, the necessary depth from the wall surface, issecured. When the casing is in position in the wall, its sides a and bwill extend slightly beyond the surface of the plaster, under normalconditions. The plate 6 is then placed in position on the protrudingends of said walls, which holds it in predetermined relation thereto,and, by using the holes in the plate as a guide, holes may be drilledthru the laths y and a, which will register with the screw threadedholes in the flanges d. The screws f are then passed thru the plate eand the laths and screwed into the flanges, so as to clamp theintervening laths and plaster between the plate and flanges, as shown inFig. 1.

Before the casing is placed in position, apertures, as 0"in Fig. 2, areformed by pushing out the partly severed portions a or c, at the pointswhere it is desired to have the conductors enter the casing. If theconductors are to be passed thru apertures in one side of the bottom,then the conductors may be drawn thru the wall opening and then passedthru the casing apertures, before the casing may be inserted while theconductors are in the apertures, otherwise, the conductors usually mustbe fished thru the apertures after the casing is in position. To do thisis usually not especially difficult if the conductors may be easilybent, but it is very diflicult to do this, in many instances when ametal encased conductor is employed.

When the installation is on a wall, the conductors almost invariably runvertically, or at right angles to the laths, so that they may beconveniently drawn thru the bottom open ings, either at one or bothsides, under the i ever, the conductors, in most instances run parallelto the floor timbers, and in 9. rec- 'tion parallel to .the-laths, sothat, if the box or 'casing is installed in the relative position to thelaths shown in Figs. 1 and 2, unless the conductors can'be sharply bentthey must be fished thru the openings in the end .walls a. The metalcovered conductors usually employed cannot be bent sufliciently topermit insertion thru the bottom apertures, and it isve diflicult tofish them thru .apertures in t e end walls a.

To obviate this difliculty, and to provide means whereby the box mayalways be set in a position in which the conductors may be drawn thruthe bottomo ings corresponding to the apertures c I provide meanswhereby the box ma be set in a position 90 from that shown in i 1 and 2,said means being illustrated in Figs. 8 to 10, and consisting of a metalbridge plate m of oblong form aving a centrally located aperture, ofapproximately the same size and shapes as that in the clamping plate e,and having the corners of its end portions rounded and adapted to extendapproximately from the middle of one lath to the middle of the lath nextbut one adjacent thereto, when placed in transverse osition thereon.

The width 0 metal between the side edges of plate m and the edges of theaperture therein is less than the distance from the holes for the screws7, in the flanges d, to the point where the flanges meet the bottom 0 ofthe box. A down-turned lip '12. is formed on the plate, at each side ofthe a erture, of somewhat less width than the thickness of a lath.

When it is desired to set the box at right angles to the position shownin Fig. 2, the plate m is passed up thru the ceiling opening in adiagonal position, the length of the diagonal of the o ening and thewidth of the plate being ma e to correspond and then the plate is placedin transverse relation on the laths so that its end portions rest on theuncut laths and its side portions on the end portions of the lath whichhas been cut, and so that the flanges 11. extend down into the ceilingopening. The conductors will then be drawn down thru the opening andpassed thru the apertures in one side of the bottom of the box and thenthe latter will be passed up thru the ceiling opening and the opening ofthe plate m in such a position that, when the box is swung down into theposition in which itis to be held, its flanges will rest on the sideportions of the plate, as shown in Figs. 8 and 9. The plate e will thenbe clamped in position, as before described, the screws 7 passing thruthe end portions of the cut lath, past the edges of the late m and intothe flanges, as already descri ed, ex-

ceptthatthe screws f pass thru the cut lath instead of thru the uncutlaths.

Under these conditions the flanges do not directly engage the laths, butindirectly enage all of them which are adjacent the open- '1ng thru theplate m and, as the latter is clamped firmly against the laths, and theflanges against the late, the box is as firmly connected to the ce1lingas if it were in the opposite position. The plate m also serves toprotect the laster as the conductors are drawn thru t e opening.

It will be apparent that, by employing theplate m, when necessary, thebox may always be set so that the conductors may be passed into it .thruthe o enings in the bevelled or rounded portion 0? the bottom, under allconditions.

When conductors are employed which are not metal covered and are passedthru either the bottom or end openings, they may be clamped in positionby clamping the frame 9 against them by means of screws 2', as indicatedin Fig. 5. If, however, metal covered conductors are employed and thewiring regulations require that the coverings be grounded, it isnecessary to provide an elec trical connection between the covering andthe box which is better than would be afforded by the frame g. As whenthe plate m is provided, it is only necessary to provide openings thruthe opposite portions of the bottom a. This permits a form of clamp tobe employed for mechanically and electrically connecting the conductorto the box. which would take up too much room therein, if arranged atall sides thereof, but which may be employed on opposite sides only.

For this class of work a slightly modified form of box or casing isemployed which is shown in Figs. 8 and 9, and principally differs fromthat already described in that the bottom 0 is flattened at the portionsthereof which are apertured, or cutawa to enable apertures to be readilyformed, while no provision whatever is made for apertures correspondingto the apertures a in the end walls, a Under these conditions, ringclamps 0 are preferably attached to the end walls, a in register withthe bottom apertures, as shown in Figs. 8 and 11, so that, when theconductors, are inserted, they will be passed thru the clamps 0, whichwill be tightened about the conductors when they have been pulled intoposition.

After the box has been secured in position, the nipple j may be set in aperpendicular position and then firmly clamped before the fixture isattached, even though the casing may be held in a somewhat tiltedposition. The fixture will be attached to the nipple in a well knownmanner, as indicated in dotted lines in Fig. 1, and, after theconnections have been made, the whole fixture support will be concealedby a suitable canopy or shield. When a switch is installed in the casingthe nipple will not be employed.

The casing sides and bottom are adapted to be stamped out of sheet metaland the whole casing may be manufactured at small expense.

It will be noted that the above described device possesses variouspractical features of advantage. The casing flanges are firmly clampedeither directly or indirectly against the back surfaces of the laths, sothat forces tending to swing the fixture will be effectively resistedthereby, and, as the clamping plate extends over a considerable area ofthe surface of the plaster, crumbling of the plaster, or other injurythereto, is unlikely to occur. The security with which the casing isattached to the wall is not dependent on the engagement of screws ornails directly with the laths and the lath, which is necessarily cut, orweakened, to enable the conductors to be passed thru the wall, is notrelied on at all to support the box, whether the bridge plate m isemployed or not. It is to be further noted that a metal wall is rovidedbetween all the adjacent wood wor of the building and the connectionswithin the casing or canopy.

While the device is primarily and especially designed for use inconnection with a lath and plaster wall or ceiling, it may also be usedto advantage in connection with an inner wall which is constructed ofwall board.

From the description given it should be evident that the improved boxproper rests wholly behind the wall when in place and has integralflanges formed therewith which bear against the wall and so carry theload of the fixture. The fixture supporting means, as will appearhereinafter, is integral with this portion of the box so that the loadon the fixture supporting means is transmitted directly to the integralflanges. The clamping plate serves to hold all of the parts in fixedrelation to the wall.

While I have shown and described the embodiment of my invention as usedfor supporting an electric light fixture, it may also be used toadvantage for supporting an electric switch, and it will be understoodthat the word fixture in the specification and claims, where the contextpermits applies equally to an electric light fixture and to an electricswitch.

- Iclaim:

An outlet box having end walls, side walls secured to the end walls andof a lesser height than the latter, whereby the end walls project beyondthe side walls, a bottom wall secured to the projecting portions of theend walls and abutting the lower edges of the side walls, flanges formedon the ends of the bottom wall and projecting at right angles to theside walls from the points at which the walls

